Submandibular Gland Transfer in the Treatment of Severe Dry Eye Syndrome

Dry eye syndrome (DES) is a very common condition characterized by ocular irritation due to a deficient tear film. In its most severe form, it can cause ulceration of the cornea with spontaneous perforation and loss of the eye.  There are many known causes of DES. They typically stem from conditions causing aqueous tear deficiency or increased evaporative losses.  The most common cause being deficient tear production, this condition can be associated or unassociated with Sjogren Syndrome.  Non-Sjogren related deficiencies include vitamin A deficiency, age related changes, and drug-induced.  Sjogren-related DES is typically caused by connective tissue diseases.  Lacrimal obstructive diseases are also included in this “aqueous tear deficiency” category and can be caused by post-radiation fibrosis, Stevens-Johnson Syndrome, or ocular pemphigoid.   On the other hand, evaporative losses causing DES occurs in the setting of facial paralysis or lid palsy, ectropion, and low blink rate. 

The tear film is crucial to protection of the globe as it functions to lubricate the ocular surface, guard against infection, and provides a refractive surface for visual acuity. Any alteration in the delicate composition of the tears results in a poor tear film that causes ocular irritation and inflammation.

Most DES patients are managed with pharmaceutical tear substitutes or minor surgical procedures such as punctum plugging or lid tarsorrhaphy. However, there exists a small subpopulation of patients who suffer from extremely dry eyes.  In these patients, routine surgical measures or medical management do not suffice to prevent complications.  Submandibular gland transfer as a treatment for DES has been studied and shown to be effective in other countries; however, the procedure is rarely used in the United States.¹

The lacrimal gland is the primary source of secretions for lubrication of the ocular contents. In the head and neck, the parotid gland and submandibular gland are also major producers of secretions in the head and neck area. Both glands produce a constant baseline secretion.  In 1986, Maurube-Del-Castillo² described submandibular gland transfer. McCloud ET al^{3, 4} then reported clinical experience in the New Zealand and Australian literature. Sieg ET al^5-8 has also popularized the procedure in the German literature. Recently, Paniello ET al¹described a small series of patients who had the procedure performed in North America.

Six submandibular glands were harvested for transfer at our institution between January, 2010 and February, 2013. Harvesting of the gland for microvascular transfer is similar to that undertaken for resecting the gland. After harvesting, the submandibular gland is placed into a temporal pocket and the duct is tunneled to the supero-lateral fornix of the eye. Microvascular anastomosis is performed and blood flow re-established to the gland. Successful transfer was achieved in 6 of the 4 transfers. In the 4 viable transfers, we have noted that patients begin to get tear production and relief of symptoms within as soon as two weeks. However, one must wait up to three months before the optimal result can be obtained. The 2 nonviable transfers failed due to progressive scarring at the supero-lateral fornix with subsequent obstruction of the duct in one case and postoperative infection in the other.

Submandibular free tissue transfer to rehabilitate patients with DES has entered the field of reconstructive surgery in the United States of America. This method has been successfully used at our institution for the management of severe DES cases resulting in a wet eye with improvement in ocular symptoms.

References

1) Paniello RC.  Submandibular gland transfer for severe xerophthalmia.  Laryngoscope 2007;117 (1):40-4.

2) Marube-del-Castillo J. Transplantation of salivary gland to the lacrimal basin. Scand. J. Rheumatol. Supp 1986;61:264.